A mask blank is provided in which a phase-shift film is provided on a transparent substrate, the phase-shift film having a predetermined transmittance to ArF exposure light and being configured to shift a phase of ArF exposure light transmitted therethrough, wherein the phase-shift film comprises a nitrogen-containing layer that is formed from a material containing silicon and nitrogen and does not contain a transition metal, and wherein a content of oxygen in the nitrogen-containing layer, when measured by X-ray photoemission spectroscopy, is below a detection limit.